Adjusting means for cinematograph projectors



ADJUSTING MEANS FQR CINEMATOGRAXH IRGJ'ECTORSv Filed sept. 1e, 1959HTTORN fys.

' 25' 'be arranged Patented June 13, 1933 UNITED 4,STATI-:s PATENTOFFICE WESLEY aam'r Jour/or m'ron max, manon, miami) USTING MEANS FOBCINEMATOGBAPH PBOJ'EUIOBS Application filed September 16, 1980, SerialNo. 482,230, and in Great Britain November 4', 1829.

v This invention relates to adjusting means A for cinematographprojectors of the type comprising a source of light; a film holder; aseries of moving lenses disposed at a xed pitch and movin with the lm,there being one lens for eac film frame; a stationary composing lens,and means defining a gate so 'as to form at said gate a single compositeimage from several adjacent 'film frames, The conjugate foci of thesystem comprising the composing lens and the moving lenses arerespectively in the film plane and in the gate. This type of projectorisused with films which are photographed by means of a camera employingthe same optical system, that is, the film pictures `are photographed byfocussing an image of the object at a gate, which ma define a simpleopening or ma include a the best use o the available lightl Behind theate is an opticalsysteln'comprising a v fixer? motion correcting lensanda series of lenses moving with the film.- Said series may between thefixed lens and the film. Each moving lens produces on the film acorresponding p otographic picture of the object,'the film plctures beinspaced equally with the moving lenses, whic are themselves theircombination as a Whole in the same direction relatively to the filmholder.

The invention is illustrated diagrammaticall in the accompanyingdrawing, in which: Fiigfl shows ther camera, and

Fig. II the projector.

Referring to Fig. I, 2 indicates a lens intended to be' el`d lens tomakes spaced at the pitch desired for the film picpresent invention this'of the film are exposed -throu h vthe aperture 11 the aperture 10. In

vby-means of which a plane image of the oblent bac are parallel. 'Behindthe lens 5 is a series of movin lenses 6, and behind 'them 60 again isthe 7 guided in the fihn gate 8. -The distance between the film and themovin lenses 6 is equal to the focal len vof sai lenses 6, so that thelatter project on to thefilm plane a series of images of the object, onefor each lens 6. The film and the lenses are moved continuously andtogether by, for example, the mechanism described in thespecifcation ofPatent No.

1,768,772. Where the object to be photo- 7 a hed is relatively close tothe camera and within the focal angle of the optical system, the gate 3and lens 2 may be omitted and masks 9 are provided to confine the raysfrom each lens to its proper film area. Apertures 10 and 11 are providedto expose several lenses 6 and several frame lengths of film at alltimes. With the gate 4 and lens 2 in use, the masks 9 ma be omitted.

If reproduction in co our is desired, the $0 film pictures arehotographed in successive similar groups o monochromes, each member ofthe group being taken with a different colour filter. In the exampleshown, the colour filters 12 are mounted 1n the cells 85 of the lenses6,

A positive reproduction of the negative film thus produced is made, andis projected by means of the'projector shown in Fig, II.

In this. case a source of light 13 is provided 90?. for illuminating thefilm 7*. Several frames simultaneously Y and the film 1s movecontinuously. In front ofthe film is provided a series of `moving lenses6" simi- 95 j i --at their focal distance from the film several lensesbeing exposed simultaneously through front: ofthe moving lenses is thefixed lens which in this case acts to superimpose the several images offilm pictures in the gate 3. Said gate is open and its distance from thelens 5 is equal 5 to the focal length of said lens. The single compositeimage thus formed in the gate 3* is projected onto the screen 14 by theprojecting lens 2. Should, however, the desired area of the screenan'dfits distance from the projector be suiiiciently small, the gate 3'*may be omitted and the screen substituted therefor.

For colour reproduction from monochromes produced as above described,sets of 15 colour filters 12a which may be similar to those of thecamera, are provided.

In order to compensate for variation in the length of the positive film,the series of lenses 6, the gate 3 andthe composing lens 5* are 2Qadjusted towards and from one another in the direction of the opticalaxis and their combination as a whole is adjusted in the same directionrelatively to the film gate 8. Adjustments for this purpose are shownschematically in Fig. II. A right and left hand screw l5 is rotatablymounted on the cell of lens 5a and its screwed ends are threadedrespectively into the casing 16 of the lens series 6 and into the gatestructure 3*. The pitches of the screw threads are in the same ratio asthe focal lengths of the lenses 6 and 5, By this means the focussingadjustment between the lenses 6*, the lens 5* and the gate 3a iseiected. Further adjustment between said parts and the film gate 8*, inorder to eect superimposition of the images in the gate 3, is effectedby an adjusting screw 17 I claim:

p 49 A cinematograph iilm projector, comprising a film holder, a seriesof moving lenses, a stationary composing lens, and a. gate in front ofthe composing lens, means securing the moving lens series, the gate andthe comf 5 posing lens to one another so that they form a unit, saidmeans being adjustable to .sh.it-,v the moving lens series and the gateaxially relatively to the composing lens roportionately'to the focallengths respectlvely of 50 the moving lens series and the composing lensand further means connecting said-unit to the lm support, said furthermeans being adjustable to shift the unit axially relatively to the filmsupport.

, In testimon whereofI aixm si ature.

ESLEY ERNES J HN.

